The reason for the material switch, according to Kuo, is both to differentiate the iPhone from rival phones that use aluminum and to boost stagnant sales.

Apple didn't immediately respond to a request for comment. KGI didn't respond to a request for a copy of Kuo's report. In the past, KGI has said regulations prevent it from distributing its research in the US.

iPhone sales growth has flattened, in part because customers resisted upgrading after last year's 6S and 6S Plus failed to include enough new features. Equipping future phones with more must-haves could help Apple put some pep in sales and compete with Samsung, as well as other phone makers.

The glass expected to be used in next year's iPhone will be tougher and more durable than the glass used in the past, Kuo said, according to AppleInsider. So the new phone's casing would stand a better chance of surviving a drop.

One drawback in Kuo's forecast is that the glass casing and AMOLED screen won't show up until 2017, rather than in Apple's expected iPhone refresh later this year. Reports so far of the coming iPhone indicate few enhancements from the current model beyond stereo speakers and a dual-camera for the larger model. Such a scenario could disappoint consumers and investors alike.

All of this remains in the rumor stage. That said, Kuo has a good track record at nailing Apple developments.